Mobile loading dock with wheel assembly

ABSTRACT

A mobile loading dock including a planar ramp member having an underside with a wheel assembly. The wheel assembly includes a tension spring, hydraulic member, a leg hingedly attached to the ramp underside and a wheel attached to the leg. The tension spring exerts a pulling force on the leg and wheel and the hydraulic member exerts a pushing force. The combined forces are directionally disposed to erect the wheel assembly when the lower end of the mobile loading dock is raised from a resting position in contact with the ground surface to a mobile position.

RELATED APPLICATION

The present application is a continuation of pending U.S. patentapplication Ser. No. 13/903,207, filed May 28, 2013, the contents ofwhich are incorporated by reference in their entireties.

FIELD

This device relates to mobile loading docks and more particularly to aloading dock having a wheel assembly for positioning of the dock.

BACKGROUND

A variety of loading docks have been devised to adjust to the height ofdifferent trailers to properly match the deck of the trailer to theheight of the dock. By aligning the height of the trailer and the dockthe loading and unloading of cargo is facilitated.

There are many such devices in the prior art. One such device is seen inU.S. Pat. No. 4,624,446 to Gould which discloses a reinforced platformpivotally mounted to the ground at one end and includes a supportassembly having hydraulic cylinders. In operation the rear wheels of atruck trailer are backed onto the platform and then the non-mounted endof the platform is lifted by the hydraulic cylinders until the deck ofthe trailer is equal to the height of the dock. A similar device isdisclosed in U.S. Pat. No. 4,765,792 to Cherry et al. which alsodiscloses a pivotally-mounted and hydraulically-raised platform.

Loading docks of the prior art typically have certain disadvantages. Themajority of moveable loading docks require at least some level of manualmanipulation by the user to move the dock into a desired position forloading and unloading of material. Typically, this requires a fork truckoperator or other individual to manually connect the ramp portion of theloading dock to a fork truck. This can be done through the use of aloosely connected chain. The individual then must get back in the forktruck, move the ramp to the desired location and then get back out ofthe fork truck to disconnect the ramp. This is a very time consumingprocess which may take more than one individual to execute.

It would be desirable to have a mobile loading dock which can beconnected and disconnected to a fork truck and moved without the needfor the user to leave the fork truck. It would also be desirable toprovide a device for connecting a loading dock and the forks on a forktruck which is secure and safe and which also allows for easymaneuvering of the loading dock.

This device overcomes certain problems and shortcomings in the priorart, including those mentioned above and others, and provides advantagesfor a mobile loading dock not previously provided.

SUMMARY

This device is an improvement in a mobile loading dock apparatus of thetype including a lower end terminating in a lower edge and an upper endincluding an upper edge. The lower edge has a slot substantiallyparallel to the length of the ramp member for engagement with aslot-engaging member. The slot-engaging member is able to be connectedto a fork truck for positioning of the ramp member.

In highly preferred embodiments, a fork-engaging sleeve is used toposition the ramp member. Preferably, the fork-engaging sleeve has anunderside from which the slot-engaging member protrudes downward. Theslot-engaging member includes a downward-protruding rod portion and aflange-end portion connected thereto.

Preferably, the slot includes a first portion and a second portion. Thefirst portion guides the slot-engaging member toward the second portionwherein the slot-engaging member is securable. It is also preferred thatthe second portion include an arc-shaped member affixed to an undersideof the ramp member for receiving the flange-end portion. It is highlypreferable that the flange-end portion include a tapered-upward-facingsurface for contact and securement with the arc-shaped member whenconnecting the fork truck to the loading dock.

In preferred embodiments, the arc-shaped member includes aconcave-interior surface for securement of the slot-engaging member andfor interaction with the tapered-upward-facing surface thereby enablingmovement of the ramp member.

In highly preferred embodiments, the fork truck includes at least onefork and the fork-engaging sleeve includes at least one sheathe forreceiving the fork. In other highly preferred embodiments, thefork-engaging sleeve includes two sheathes, one for each correspondingfork. Another aspect of the device includes a chain for supplementarysecurement of the fork-engaging sleeve to the fork truck.

It is highly preferable that the ramp member has opposed sidewalls andthe lower edge has edge-end corners. Preferably, the sidewalls extendfrom the upper edge of the ramp member to termination points between theupper edge and the edge-end corners; the distance between thetermination points and the edge-end corners is between 12 inches and 60inches.

It is preferable that the ramp member include (a) a first upper-endplanar portion, the plane of which is parallel to a ground surface onwhich the ramp member rests; and (b) a second planar portion, the planeof which is downwardly-angled from the upper end to the lower edge. Someembodiments also include a hand-rail secured to the first upper-endplanar portion.

It is highly preferred that the mobile loading dock includes a rampunderside with a wheel assembly. In preferred embodiments, the wheelassembly includes a tension spring, a hydraulic member, a leg hingedlyattached to the ramp underside and a wheel attached to a leg at an axleand disposed to contact the ground surface beneath the mobile loadingdock.

In operation, the tension spring exerts a pulling force on the leg andwheel and the hydraulic member simultaneously exerts a pushing force onthe leg and wheel. The combined pulling force and pushing force aredirectionally disposed to erect the wheel assembly when the lower end ofthe mobile loading dock is raised from a resting position in contactwith the ground surface to a mobile position not in contact with theground surface.

Preferably, the wheel assembly includes a hydraulic check valve forautomatic locking of the wheel assembly into a mobile position when thewheel assembly is erected. The wheel assembly also preferably includes amanually-actuated hydraulic release valve. Actuation of the releasevalve while in the mobile position causes the pushing force to bereduced and the wheel assembly to return to the resting position.

It is preferred that the wheel assembly also include an elongateweight-bearing support member having a first end attached to the rampunderside and a second end attached to a tension spring and having afoot. The foot contacts the ground surface when the wheel assembly is inthe resting position. When in the resting position, the support memberbears a portion of the weight of the ramp member.

It is highly preferred that the ramp member include two wheelassemblies, one on each side of the ramp. The wheel assemblies areequally distant from a point on the lower edge and are located on eachside of ramp member to provide stability.

BRIEF DESCRIPTION OF THE DRAWINGS

The drawings illustrate a preferred embodiment including the above-notedcharacteristics and features of the device. The device will be readilyunderstood from the descriptions and drawings. In the drawings:

FIG. 1 is a perspective view of the mobile loading dock and fork truckwith fork-engaging sleeve;

FIG. 2 is a perspective view of the fork-engaging sleeve of FIG. 1;

FIG. 3 is a perspective view of the fork-engaging sleeve engaged withthe loading dock of FIG. 1;

FIG. 4 is a cross sectional view of the mobile loading dock andfork-engaging sleeve of FIG. 2 taken along line 4-4;

FIG. 5 is a cross-sectional view of the fork-engaging sleeve partiallyengaged with the loading dock of FIG. 1;

FIG. 6 is a cross-sectional view of the fork-engaging sleeve partiallyengaged with the loading dock of FIG. 1;

FIG. 7 is a cross sectional view of the mobile loading dock andfork-engaging sleeve of FIG. 3 taken along line 7-7;

FIG. 8 is a cross-sectional view of the fork-engaging sleeve fullyengaged with the loading dock of FIG. 1;

FIG. 9 is a perspective view of the slot-engaging member;

FIG. 10 is a perspective view of the arc-shaped member;

FIG. 11 is a perspective view of the mobile loading dock and fork truckof FIG. 1;

FIG. 12 is a perspective view of the mobile loading dock of FIG. 1 withthe ramp member in the raised position;

FIG. 13 is a perspective view of the mobile loading dock of FIG. 1 withthe ramp member in the lowered position;

FIG. 14 is a sectional view of the wheel assembly of FIG. 11 taken alongline 11-11;

FIG. 15 is a sectional view of the wheel assembly of FIG. 12 taken alongline 12-12; and

FIG. 16 is a sectional view of the wheel assembly of FIG. 13 taken alongline 13-13.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

FIGS. 1-16 illustrate a mobile loading dock 10 with planar ramp member12. Mobile loading dock 10 includes a lower end 14 terminating in alower edge 16 and an upper end 18 having an upper edge 20. Lower edge 16has a slot 22 substantially parallel to the length of the ramp memberfor engagement with a slot-engaging member 24. Slot-engaging member 24is able to be connected to a fork truck 26 for positioning of rampmember 12.

FIG. 1 illustrates fork truck 26 connected to ramp member 12 via afork-engaging sleeve 28. Fork-engaging sleeve 28 is used to positionramp member 12. FIGS. 4-8 illustrate that Fork-engaging sleeve 28 has anunderside 30 from which slot-engaging member 24 protrudes downward.Slot-engaging member 24 includes two parts, a downward-protruding rodportion 32 and a flange-end portion 34 as seen in FIGS. 4-9.

As illustrated in FIG. 2, slot 22 includes a first portion 36 and asecond portion 38. First portion 36 guides slot-engaging member 24toward the second portion 38. Slot-engaging member 24 is secured insecond portion 38. Second portion 38 includes an arc-shaped member 40affixed to the underside 30 of ramp member 12 for receiving theflange-end portion 34 of slot-engaging member. Flange-end portion 34include a tapered-upward-facing surface 42. Arc-shaped member 40includes a concave-interior surface 44 (as seen best in FIG. 10) forsecurement of slot-engaging member 24 and for interaction withtapered-upward-facing surface 42 thereby enabling movement of rampmember 12.

It is the interaction between flange-end portion 34 (specifically thetapered-upward-facing surface 42) and arc-shaped member 40 that securesramp member 12 with fork truck 26 and allows fork truck 26 to move andposition the ramp member 12.

Fork truck 26 includes at least one fork 46 and preferably two forks 46as seen in FIGS. 2-3. As also illustrated in FIGS. 2-3, fork-engagingsleeve 28 includes at least one sheathe 48 for receiving one fork 46 ortwo connected sheathes 48 if there are two forks 46. Sheathe 48 slideson to the fork(s) 46 and is held in place through frictional engagement.A chain 50 can be used for supplementary securement of fork-engagingsleeve 28 to fork truck 26 as seen in FIGS. 2-3.

FIGS. 1 and 11-13 illustrate that ramp member 12 has opposed sidewalls52 that run the majority of the length of ramp member 12. Lower edge 16of ramp member 12 has edge-end corners 54. (See FIG. 1.) The edge-endcorners 54 are located at the end of ramp member 12. Sidewalls 52 onramp member 12 extend from upper edge 18 to termination points 56.Termination points 56, as seen in FIG. 1, are located between 20 upperedge of ramp member 12 and edge-end corners 54. The distance betweentermination points 56 and the edge-end corners 54 is between 12 inchesand 60 inches.

Ramp member 12 has several different planes as seen in FIGS. 1 and11-13. These include a first upper-end planar portion 58, the plane 64of which is parallel to a ground surface on which ramp member 12 rests;and a second planar portion 60, the plane 66 of which isdownwardly-angled from upper end 18 to lower edge 16. Some embodimentsof ramp member 12 also include a hand-rail 62 secured to first upper-endplanar portion 58 as seen in FIG. 1. First upper-end planar portion 58is the section of ramp member 12 which, when in use, abuts either aloading dock or vehicle for purposes of loading or unloading.

Typically loading docks include a raised dock for the loading andunloading of materials which often come in large quantities and arecarried by wooden pallets. Most docks have doorways with overhead doorsthat provide access to a garage or similar type of building.

FIG. 1 also illustrates that ramp member 12 includes stationary supportmembers 68 which do not articulate but which assist in supporting theweight of the fork truck 26 so that personnel and material handlingequipment (such as a fork truck 26), can conveniently move between theloading dock and the truck bed. A manual hand crank is traditionallyused to raise or lower the height of the stationary support members 68.

As also seen in FIG. 1, mobile loading dock 10 includes a ramp underside70 with a wheel assembly 72. FIGS. 11-16 illustrate that wheel assembly72 has a tension spring 74, a hydraulic member 76, a leg 78 hingedlyattached to the ramp underside 70 and a wheel 80 attached to leg 78 atan axle 82 and disposed to contact a ground surface 84 beneath mobileloading dock 10.

In operation, tension spring 74 exerts a pulling force on leg 78 andwheel 80 and the hydraulic member 76 exerts a pushing force on the leg78 and wheel 80 as seen by the arrow in FIGS. 12 and 15. The combinedpulling force and pushing force being directionally disposed to erectwheel assembly 72 when the lower end 14 of mobile loading dock 10 israised from a resting position in contact with ground surface 84 (FIGS.12 and 15) to a mobile position not in contact with ground surface 84.

Wheel assembly 72 includes a hydraulic check valve 86 for automaticlocking of wheel assembly 72 into a mobile position when wheel assembly72 is erected. Wheel assembly 72 also includes a manually-actuatedhydraulic release valve 88, actuation of which in the mobile positioncauses the pushing force to be reduced and wheel assembly 72 to returnto the resting position as seen in FIGS. 11, 13-14 and 16.

As seen best in FIGS. 14-16, wheel assembly 72 also includes an elongateweight-bearing support member 90 having a first end 92 attached to rampunderside 70 and a second end 94 attached to tension spring 74 andhaving a foot 96. Foot 96 contacts ground surface 84 when wheel assembly72 is in the resting position. When in the resting position, supportmember 90 bears a portion of the weight of ramp member 12.

Ramp member 12 typically includes two wheel assemblies (two not shown)which are equally distant from a point on the lower edge 16 and locatedon each side of ramp member 12 to provide stability.

In operation, mobile loading dock 10 is moved from a resting to a mobileposition by fork truck 26 so that it directly contacts either a dock ora semi-trailer for loading and unloading of material. In order tofacilitate movement of mobile loading dock 10, fork truck 26, whichalready has the fork-engaging sleeve 28 on its forks 46, drives forwardtowards the lower end 14 of ramp member 12 until slot-engaging member 24engages slot 22. Fork truck 26 then slowly raises the forks 46 straightup and engages flange-end portion 34 with arc-shaped member 40 therebysecuring the connection between the fork truck 26 and the loading dock10 without the need for manual operation by user. When loading dock 10is secured to fork truck 26, fork truck 26 can lift up lower end 14 oframp member 10 and manipulate movement of ramp member 12 in variousdirections until ramp member 12 is in the desired position.

Fork truck 26 can turn and maneuver loading dock 10 in 90° in eitherdirection given the opposed sidewalls 52 and the correspondingtermination points 56. The plurality of possible angles defines acircular arc around lower edge 16 of ramp member 12, the arc subtendingan angle greater than 180° and having a center point defined byslot-engaging member 24. Slot-engaging member 24 moving axially withinsecond portion 38 of slot 22 facilitates positional movement of forktruck 26 between any of a plurality of possible angles relative tomobile loading dock 10 in the mobile position and further facilitatesfork-truck-driven movement of mobile loading dock 10 infork-truck-determined directions measurable on an x-axis on the groundsurface and a perpendicular y-axis on the ground surface.

As lower end 14 of loading dock 10 is lifted off of the ground 84 into amobile position, tension spring 74 automatically articulates wheelassembly 72 into the mobile position. Hydraulic member 76 suctions fluidfrom a tank and a check valve 86 holds hydraulic member 76 in the fullyextended position, allowing loading dock 10 to be moved without anyhuman effort on the hydraulic system (no pumping). Fully automaticlatching and articulation of loading dock 10 is achieved. Once loadingdock 10 is moved into the desired position, loading or unloading ofmaterial can begin.

The operator of the fork truck 26 has the ability to pivot the entireloading dock 10 about the wheel assembly 72. When the weight of loadingdock 10 is removed as ramp member 12 is lifted, the tension spring 74will put a force onto the wheel 80, causing the hydraulic member 76 tobe mechanically extended as the wheel assembly 72 rotates from the forceor tension spring 74. Check valve 86 allows hydraulic fluid to besuctioned from the bottom of a hydraulic tank into cylinders. When forktruck operator lowers the lower end 14, the wheel 80 is moved by thetension spring 74 into position and is held in place by the hydraulicmember 76 (specifically a hydraulic cylinder).

A wide variety of materials are available for the various partsdiscussed and illustrated herein. Although the device has been describedin conjunction with specific embodiments thereof, it is evident thatmany alternatives, modifications and variations will be apparent tothose skilled in the art. Accordingly, it is intended to embrace allsuch alternatives, modifications and variations that fall within thespirit and broad scope of the appended claims.

The invention claimed is:
 1. A mobile loading dock comprising a planarramp member having: a lower end terminating in a lower edge; an upperend including an upper edge; and a ramp underside having a wheelassembly thereupon, the wheel assembly having (a) a tension spring; (b)a hydraulic member; (c) a leg hingedly attached to the ramp underside;and (d) a wheel attached to the leg at an axle and disposed to contact aground surface beneath the mobile loading dock.
 2. The mobile loadingdock of claim 1 wherein the tension spring exerts a pulling force on theleg and the wheel and the hydraulic member exerts a pushing force on theleg and the wheel.
 3. The mobile loading dock of claim 2 wherein thecombined pulling force and pushing force are directionally disposed toerect the wheel assembly when the lower end of the mobile loading dockis raised from a resting position in contact with the ground surface toa mobile position not in contact with the ground surface.
 4. The mobileloading dock of claim 1 wherein the wheel assembly further includes ahydraulic check valve for automatic locking of the wheel assembly into amobile position when the wheel assembly is erected.
 5. The mobileloading dock of claim 4 wherein the wheel assembly further includes amanually-actuated hydraulic release valve, actuation of which in themobile position causes the pushing force to be reduced and the wheelassembly to return to the resting position.
 6. The mobile loading dockof claim 5 wherein the wheel assembly further includes an elongateweight-bearing support member having a first end attached to the rampunderside and a second end attached to the tension spring and having afoot, the foot contacts the ground surface when the wheel assembly is inthe resting position, whereby the support member bears a portion of theweight of the ramp member.
 7. The mobile loading dock of claim 1 whereinthe lower edge includes a slot substantially parallel to the length ofthe ramp member for engagement with a slot-engaging member whereby theslot-engaging member is connectable to a fork truck fork for positioningof the ramp member.
 8. The mobile loading dock of claim 7 furtherincluding a fork-engaging sleeve having a sleeve underside from whichthe slot-engaging member protrudes downward, the slot-engaging memberhaving a downward-protruding rod portion and a flange-end portionconnected thereto.
 9. The mobile loading dock of claim 8 wherein theslot includes a first portion and a second portion, the first portionfor guiding the slot-engaging member toward the second portion whereinthe slot-engaging member is securable.
 10. The mobile loading dock ofclaim 9 wherein the second portion includes an arc-shaped member affixedto the ramp underside, the arc-shaped member for receiving theflange-end portion.
 11. The mobile loading dock of claim 10 wherein theflange-end portion includes a tapered-upward-facing surface and thearc-shaped member includes a concave-interior surface for securement ofthe slot-engaging member, the concave-interior surface being configuredfor interaction with the tapered-upward-facing surface thereby enablingmovement of the ramp member.
 12. The mobile loading dock of claim 1wherein the ramp member includes (a) a first upper-end planar portion,the plane of which is parallel to a ground surface on which the rampmember rests; and (b) a second planar portion, the plane of which isdownwardly-angled from the upper end to the lower edge.
 13. The mobileloading dock of claim 6 wherein the ramp member includes two wheelassemblies, the two wheel assemblies being equally distant from a pointon the lower edge.
 14. The mobile loading dock of claim 1 wherein theplanar ramp member includes a stationary support member, the stationarysupport member being hydraulically or pneumatically raised or lowered.15. A method of moving a mobile loading dock from a resting position toa mobile position, the method comprising: (a) providing a planar rampmember with a lower end terminating in a lower edge; an upper endincluding an upper edge; and a ramp underside having a wheel assemblythereupon, the wheel assembly having (i) a tension spring; (ii) ahydraulic member; (iii) a leg hingedly attached to the ramp underside;and (iv) a wheel attached to the leg at an axle and disposed to contacta ground surface beneath the mobile loading dock; (b) connecting aslot-engaging member of a fork truck by engaging a fork with afork-engaging sleeve; (c) moving the fork truck to effectuate engagementof the slot-engaging member with a slot; and (d) lifting the fork andcausing the sleeve and the slot-engaging member to be lifted, therebyraising a lower end of the mobile loading dock from the resting positionto the mobile position in which the wheel assembly is erected, the fork,sleeve and slot-engaging member bearing a portion of weight of themobile loading dock.
 16. The method of claim 15 further including: (a)connecting the slot-engaging member of the fork truck by engaging thefork with the fork-engaging sleeve; (b) moving the fork truck toeffectuate engagement of the slot-engaging member with the slot; (c)lifting the fork and causing the sleeve and the slot-engaging member tobe lifted, thereby raising the lower end of the mobile loading dock fromthe resting position to the mobile position in which the wheel assemblyis erected, the fork, sleeve and slot-engaging member in combinationbearing a portion of weight of the mobile loading dock; (d) driving andsteering the fork truck in a forward or a backward direction, therebycausing the wheel of the wheel assembly to roll a forward or a backwarddistance on the ground surface; and (e) steering the fork truck in arightward or leftward direction; wherein the slot-engaging member movingaxially within the second portion of the slot facilitates positionalmovement of the fork truck between any of a plurality of possible anglesrelative to the mobile loading dock in the mobile position and furtherfacilitates fork-truck-driven movement of the mobile loading dock infork-truck-determined directions measurable on an x-axis on the groundsurface and a perpendicular y-axis on the ground surface.
 17. The methodof claim 16 wherein the ramp member includes the two wheel assemblies,the two wheel assemblies being erected at the same time when the lowerend of the mobile loading dock is raised from the resting position tothe mobile position.
 18. The method of claim 16 wherein the plurality ofpossible angles defines a circular arc around the lower edge of the rampmember, the arc subtending an angle greater than 180° and having acenter point defined by the slot-engaging member.